Question

1. Compare and contrast OSI and TCP/IP network models.
2. Differentiate between same-layer interactions and adjacent-layer interactions in network models (applicable for both TCP/IP and OSI models), and specify why each type of interaction is required in networking.
3. Explain what is data encapsulation and why is it required in computer networking.
4. Convert the following physical and logical addresses to the required formats:
   • MAC Address: AD:6F:23:4C:9B:EE to the equivalent binary
   • IP Address: 11000000.10010001.00011010.00000100 to the equivalent decimal

Answer 1

OSI MODEL

1.its full form is open system interconnection

2.it is a theoretical model consisting of 7 layers for network communication between communicating devices

i.e. application, presentation,session,transport,network,data link,physical layers and each layer having different function.

3.it is introduced by ISO(international standard organisation) with vertical approach and bottom-up approach between layers.

4.the main of designing OSI MODEL is to develop digital communicating hardwares and Softwares so that both hardwares and softwrae can communicate with each other and cooperate each other while data transfer.

TCP/IP MODEL

1.its full form is transmission control protocol/internet control protocol model.

2.it is a client server model consisting of 4 layers for data communication i.e. application layer,transport layer,internet layer,network interface layer and each layer having identical function having protocols for each layer i.e. TCP,UDP,IP,ARP,ICMP etc.

3.it is developed by Department Of Defence with horizontal approach and top to bottom approach.

4.unlike OSI model it is a practical model and developed much before the OSI model.here application,presentation and session layer combined together to form application layer in TCP/IP model and datalink,physical layer comined to network interface layer,the main aim of this model is to create a end to end connection so that data can transfer smoothly through the internet

so at the end we can say

1. OSI model mainly concerns over services,protcols and interfaces and gives clear difference between them and here TCP/IP model fails to give the clarity.

2. TCP/IP model more reliable than OSI model because it is flexible,tangible and robust.

SAME LAYER INTERACTION

when two communicating devices work upon the same layer and single protocol they just ignore how the data behaved in other lower or higher layers for example we can take an example of web server and  web server both are working on application layer so they just ignore how the data is transporting by the network system layers.

ADJECENT LAYER INTERACTION

this means each lower layer provides service to the layer present above it to pass the error free and smooth data passing.

both same layer and adjacent layer interactions are needed because in a network system sometime it makes horizontal communication between two same layer using single protocol and some time it depends upon the vertical approach of layers to pass the error free data between each layer so both the interaction are required.

DATA ENCAPSULATION

when data passes from a higher layer to a lower layer in networking model it attaches a header and some times also a trailer to the data packets this process is known as data encapsulation. the higher layer encapsulated data is also known as client data. again when the data passes from lower to higher level in receiving end of network the layers pops off the headers .this process is known as de encapsulation.both the encapsulation and de-encapsulation are regular process in networking model while sending and receiving the data.

the equivalent binary  of the mac address

AD:6F:23:4C:9B:EE=10101101:1101111:100011:1001100:10011011:11101110

IP address to decimal

11000000.10010001.00011010.00000100 = 192.145.26.4